I have 45 photos of a long contract and the tool takes 20 at a time; how do I end up with a single PDF?

Why 20 images at a time?

The tested limit in Images to PDF is 20 images, with up to 20 MB and 50 megapixels per image. The PDF is built inside your browser and every image sits in the device's memory until the build finishes, so on phones especially, many large photos can slow the job down or stop it. If you select more than 20 at once, the tool keeps the first 20 and shows a message that the rest were ignored, so do not assume the file is complete.

Before you start: prepare the photos

The classic mistake with long contracts is not in the conversion but a page that goes missing or appears twice. First put all the photos in one folder with sequential names such as 01 to 45, and confirm there really are 45. If the paper pages are numbered, compare the page number with the photo number.

Steps

1. Batch one: add photos 01 to 20, set the options once, for example A4, Fit inside and a 10 mm margin, build the file and name it part1.
2. Press reset to empty the list. Reset clears only the images and leaves the settings alone, but if you reload the page, check them again before the next batch.
3. Batch two: photos 21 to 40 with the same settings; name the file part2.
4. Batch three: photos 41 to 45; name it part3. Just five pages, which is fine.
5. Open Merge PDFs, add part1, part2 and part3 in that order, and merge them into one file.
6. Open the final PDF and check three spots: page 20 then 21, page 40 then 41, and that the last page is 45.

Why the settings must match between batches

If part one is A4 and part two is Letter, or uses a different margin, a reader will notice a jump in page size or text position at page 21, and a printer may output the parts at different sizes. A contract should look like one document scanned in one go, so write your settings down before the first batch.

Another option if the file gets too big

Forty five phone photos can produce a very large final PDF, because the tool does not compress images. If the contract is going by email or to an upload portal, compress the photos before converting, or consider sending it as three numbered files rather than one huge file the mail server will refuse.